src/main/java/net/pterodactylus/demoscenemusic/data/DataManager.java

   1 /*
   2  * DemosceneMusic - DataManager.java - Copyright © 2012 David Roden
   3  *
   4  * This program is free software: you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your option) any later version.
   8  *
   9  * This program is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12  * GNU General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16  */
  17
  18 package net.pterodactylus.demoscenemusic.data;
  19
  20 import java.sql.ResultSet;
  21 import java.sql.SQLException;
  22 import java.util.Collection;
  23 import java.util.List;
  24 import java.util.concurrent.Callable;
  25
  26 import net.pterodactylus.util.collection.Memoizer;
  27 import net.pterodactylus.util.database.Database;
  28 import net.pterodactylus.util.database.DatabaseException;
  29 import net.pterodactylus.util.database.Field;
  30 import net.pterodactylus.util.database.Join;
  31 import net.pterodactylus.util.database.Join.JoinType;
  32 import net.pterodactylus.util.database.ObjectCreator;
  33 import net.pterodactylus.util.database.OrderField;
  34 import net.pterodactylus.util.database.Parameter.StringParameter;
  35 import net.pterodactylus.util.database.Query;
  36 import net.pterodactylus.util.database.Query.Type;
  37 import net.pterodactylus.util.database.ValueField;
  38 import net.pterodactylus.util.database.ValueFieldWhereClause;
  39
  40 /**
  41  * Interface between the database and the application.
  42  *
  43  * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
  44  */
  45 public class DataManager {
  46
  47         /** The artist object creator. */
  48         @SuppressWarnings("synthetic-access")
  49         private final ObjectCreator<Artist> artistCreator = new ArtistCreator();
  50
  51         /** The group object creator. */
  52         @SuppressWarnings("synthetic-access")
  53         private final ObjectCreator<Group> groupCreator = new GroupCreator();
  54
  55         /** The track object creator. */
  56         @SuppressWarnings("synthetic-access")
  57         private final ObjectCreator<Track> trackCreator = new TrackCreator();
  58
  59         /** The style object creator. */
  60         @SuppressWarnings("synthetic-access")
  61         private final ObjectCreator<Style> styleCreator = new StyleCreator();
  62
  63         /** The database. */
  64         private final Database database;
  65
  66         /**
  67          * Creates a new data manager.
  68          *
  69          * @param database
  70          *            The database to operate on
  71          */
  72         public DataManager(Database database) {
  73                 this.database = database;
  74         }
  75
  76         /**
  77          * Returns all artists.
  78          *
  79          * @return All artists
  80          * @throws DatabaseException
  81          *             if a database error occurs
  82          */
  83         public Collection<Artist> getAllArtists() throws DatabaseException {
  84                 Query query = new Query(Type.SELECT, "ARTISTS");
  85                 query.addField(new Field("ARTISTS.*"));
  86                 return database.getMultiple(query, artistCreator);
  87         }
  88
  89         /**
  90          * Returns the artist with the given ID.
  91          *
  92          * @param id
  93          *            The ID of the artist
  94          * @return The artist with the given ID, or {@code null} if there is no
  95          *         artist with the given ID
  96          * @throws DatabaseException
  97          *             if a database error occurs
  98          */
  99         public Artist getArtistById(String id) throws DatabaseException {
 100                 Query query = new Query(Type.SELECT, "ARTISTS");
 101                 query.addField(new Field("ARTISTS.*"));
 102                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("ARTISTS.ID", new StringParameter(id))));
 103                 return database.getSingle(query, artistCreator);
 104         }
 105
 106         /**
 107          * Returns all artists that belong to the group with the given ID.
 108          *
 109          * @param groupId
 110          *            The ID of the group
 111          * @return All artists belonging to the given group
 112          * @throws DatabaseException
 113          *             if a database error occurs
 114          */
 115         public Collection<Artist> getArtistsByGroup(String groupId) throws DatabaseException {
 116                 Query query = new Query(Type.SELECT, "ARTISTS");
 117                 query.addField(new Field("ARTISTS.*"));
 118                 query.addJoin(new Join(JoinType.INNER, "GROUP_ARTISTS", new Field("ARTISTS.ID"), new Field("GROUP_ARTISTS.ARTIST")));
 119                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("GROUP_ARTISTS.GROUP_", new StringParameter(groupId))));
 120                 return database.getMultiple(query, artistCreator);
 121         }
 122
 123         /**
 124          * Returns all artists involved in the track with the given ID.
 125          *
 126          * @param trackId
 127          *            The ID of the track
 128          * @return All artists involved in the track, in preferred order
 129          * @throws DatabaseException
 130          *             if a database error occurs
 131          */
 132         public List<Artist> getArtistsByTrack(String trackId) throws DatabaseException {
 133                 Query query = new Query(Type.SELECT, "ARTISTS");
 134                 query.addField(new Field("ARTISTS.*"));
 135                 query.addJoin(new Join(JoinType.INNER, "TRACK_ARTISTS", new Field("TRACK_ARTISTS.ARTIST"), new Field("ARTISTS.ID")));
 136                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_ARTISTS.TRACK", new StringParameter(trackId))));
 137                 query.addOrderField(new OrderField(new Field("TRACK_ARTISTS.DISPLAY_ORDER")));
 138                 return database.getMultiple(query, artistCreator);
 139         }
 140
 141         /**
 142          * Returns all remix artists involved in the track with the given ID.
 143          *
 144          * @param trackId
 145          *            The ID of the track
 146          * @return All remix artists involved in the track, in preferred order
 147          * @throws DatabaseException
 148          *             if a database error occurs
 149          */
 150         public List<Artist> getRemixArtistsByTrack(String trackId) throws DatabaseException {
 151                 Query query = new Query(Type.SELECT, "ARTISTS");
 152                 query.addField(new Field("ARTISTS.*"));
 153                 query.addJoin(new Join(JoinType.INNER, "TRACK_REMIX_ARTISTS", new Field("TRACK_REMIX_ARTISTS.ARTIST"), new Field("ARTISTS.ID")));
 154                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_REMIX_ARTISTS.TRACK", new StringParameter(trackId))));
 155                 query.addOrderField(new OrderField(new Field("TRACK_REMIX_ARTISTS.DISPLAY_ORDER")));
 156                 return database.getMultiple(query, artistCreator);
 157         }
 158
 159         /**
 160          * Returns the track with the given ID.
 161          *
 162          * @param id
 163          *            The ID of the track
 164          * @return The track with the given ID, or {@code null} if there is no such
 165          *         track
 166          * @throws DatabaseException
 167          *             if a database error occurs
 168          */
 169         public Track getTrackById(String id) throws DatabaseException {
 170                 Query query = new Query(Type.SELECT, "TRACKS");
 171                 query.addField(new Field("TRACKS.*"));
 172                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACKS.ID", new StringParameter(id))));
 173                 return database.getSingle(query, trackCreator);
 174         }
 175
 176         /**
 177          * Returns all tracks by the artist with the given ID.
 178          *
 179          * @param artistId
 180          *            The ID of the artist
 181          * @return All tracks by the given artist
 182          * @throws DatabaseException
 183          *             if a database error occurs
 184          */
 185         public Collection<Track> getTracksByArtist(String artistId) throws DatabaseException {
 186                 Query query = new Query(Type.SELECT, "TRACKS");
 187                 query.addField(new Field("TRACKS.*"));
 188                 query.addJoin(new Join(JoinType.INNER, "TRACK_ARTISTS", new Field("TRACKS.ID"), new Field("TRACK_ARTISTS.TRACK")));
 189                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_ARTISTS.ARTIST", new StringParameter(artistId))));
 190                 return database.getMultiple(query, trackCreator);
 191         }
 192
 193         /**
 194          * Returns all groups the artist with the given ID belongs to.
 195          *
 196          * @param artistId
 197          *            The ID of the artist
 198          * @return All groups the artist belongs to
 199          * @throws DatabaseException
 200          *             if a database error occurs
 201          */
 202         public Collection<Group> getGroupsByArtist(String artistId) throws DatabaseException {
 203                 Query query = new Query(Type.SELECT, "GROUPS");
 204                 query.addField(new Field("GROUPS.*"));
 205                 query.addJoin(new Join(JoinType.INNER, "GROUP_ARTISTS", new Field("GROUPS.ID"), new Field("GROUP_ARTISTS.GROUP_")));
 206                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("GROUP_ARTISTS.ARTIST", new StringParameter(artistId))));
 207                 return database.getMultiple(query, groupCreator);
 208         }
 209
 210         /**
 211          * Returns all styles for the track with the given ID.
 212          *
 213          * @param trackId
 214          *            The ID of the track
 215          * @return All styles for the given track
 216          * @throws DatabaseException
 217          *             if a database error occurs
 218          */
 219         public Collection<Style> getStylesByTrack(String trackId) throws DatabaseException {
 220                 Query query = new Query(Type.SELECT, "STYLES");
 221                 query.addField(new Field("STYLES.*"));
 222                 query.addJoin(new Join(JoinType.INNER, "TRACK_STYLES", new Field("STYLES.ID"), new Field("TRACK_STYLES.STYLE")));
 223                 query.addWhereClause(new ValueFieldWhereClause(new ValueField("TRACK_STYLES.TRACK", new StringParameter(trackId))));
 224                 return database.getMultiple(query, styleCreator);
 225         }
 226
 227         /**
 228          * {@link Artist} implementation that retrieves some attributes (such as
 229          * {@link #getGroups()}, and {@link #getTracks()}) from the
 230          * {@link DataManager} on demand.
 231          *
 232          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 233          */
 234         private class LazyArtist extends DefaultArtist {
 235
 236                 /** Memoizer for the tracks by this artist. */
 237                 private final Memoizer<Void> tracksMemoizer = new Memoizer<Void>(new Callable<Void>() {
 238                         @Override
 239                         public Void call() throws DatabaseException {
 240                                 if (!hasValue("tracks")) {
 241                                         getValue("tracks", Collection.class).set(getTracksByArtist(getId()));
 242                                 }
 243                                 return null;
 244                         }
 245                 });
 246
 247                 /** Memoizer for the groups of this artist. */
 248                 private final Memoizer<Void> groupsMemoizer = new Memoizer<Void>(new Callable<Void>() {
 249
 250                         @Override
 251                         public Void call() throws Exception {
 252                                 if (!hasValue("groups")) {
 253                                         getValue("groups", Collection.class).set(getGroupsByArtist(getId()));
 254                                 }
 255                                 return null;
 256                         }
 257
 258                 });
 259
 260                 /**
 261                  * Creates a new lazy artist.
 262                  *
 263                  * @param id
 264                  *            The ID of the artist
 265                  */
 266                 public LazyArtist(String id) {
 267                         super(id);
 268                 }
 269
 270                 //
 271                 // DEFAULTARTIST METHODS
 272                 //
 273
 274                 /**
 275                  * {@inheritDoc}
 276                  */
 277                 @Override
 278                 public Collection<Group> getGroups() {
 279                         groupsMemoizer.get();
 280                         return super.getGroups();
 281                 }
 282
 283                 /**
 284                  * {@inheritDoc}
 285                  */
 286                 @Override
 287                 public Collection<Track> getTracks() {
 288                         tracksMemoizer.get();
 289                         return super.getTracks();
 290                 }
 291
 292         }
 293
 294         /**
 295          * {@link ObjectCreator} implementation that can create {@link Artist}
 296          * objects. This specific class actually creates {@link LazyArtist}
 297          * instances.
 298          *
 299          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 300          */
 301         private class ArtistCreator implements ObjectCreator<Artist> {
 302
 303                 /**
 304                  * {@inheritDoc}
 305                  */
 306                 @Override
 307                 public Artist createObject(ResultSet resultSet) throws SQLException {
 308                         return new LazyArtist(resultSet.getString("ARTISTS.ID")).setName(resultSet.getString("ARTISTS.NAME"));
 309                 }
 310
 311         }
 312
 313         /**
 314          * {@link Group} implementation that retrieves some attributes (such as
 315          * {@link #getArtists()}) from the {@link DataManager} on demand.
 316          *
 317          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 318          */
 319         private class LazyGroup extends DefaultGroup {
 320
 321                 /** Memoizer for the artist. */
 322                 private final Memoizer<Void> artistsMemoizer = new Memoizer<Void>(new Callable<Void>() {
 323
 324                         @Override
 325                         public Void call() throws Exception {
 326                                 if (!hasValue("artists")) {
 327                                         getValue("artists", Collection.class).set(getArtistsByGroup(getId()));
 328                                 }
 329                                 return null;
 330                         }
 331
 332                 });
 333
 334                 /**
 335                  * Creates a new lazy group.
 336                  *
 337                  * @param id
 338                  *            The ID of the group
 339                  */
 340                 public LazyGroup(String id) {
 341                         super(id);
 342                 }
 343
 344                 //
 345                 // DEFAULTGROUP METHODS
 346                 //
 347
 348                 /**
 349                  * {@inheritDoc}
 350                  */
 351                 @Override
 352                 public Collection<Artist> getArtists() {
 353                         artistsMemoizer.get();
 354                         return super.getArtists();
 355                 }
 356
 357         }
 358
 359         /**
 360          * {@link ObjectCreator} implementation that can create {@link Group}
 361          * objects. This specific implementation creates {@link LazyGroup}
 362          * instances.
 363          *
 364          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 365          */
 366         private class GroupCreator implements ObjectCreator<Group> {
 367
 368                 /**
 369                  * {@inheritDoc}
 370                  */
 371                 @Override
 372                 public Group createObject(ResultSet resultSet) throws SQLException {
 373                         return new LazyGroup(resultSet.getString("GROUPS.ID")).setName(resultSet.getString("GROUPS.NAME")).setUrl(resultSet.getString("GROUPS.URL"));
 374                 }
 375
 376         }
 377
 378         /**
 379          * {@link Track} implementation that retrieves some attributes (such as
 380          * {@link #getArtists()}, and {@link #getStyles()}) from the
 381          * {@link DataManager} on demand.
 382          *
 383          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 384          */
 385         private class LazyTrack extends DefaultTrack {
 386
 387                 /** Memoizer for the artists. */
 388                 private final Memoizer<Void> artistsMemoizer = new Memoizer<Void>(new Callable<Void>() {
 389
 390                         @Override
 391                         public Void call() throws Exception {
 392                                 if (!hasValue("artists")) {
 393                                         getValue("artists", List.class).set(getArtistsByTrack(getId()));
 394                                 }
 395                                 return null;
 396                         }
 397
 398                 });
 399
 400                 /** Memoizer for the styles. */
 401                 private final Memoizer<Void> stylesMemoizer = new Memoizer<Void>(new Callable<Void>() {
 402
 403                         @Override
 404                         public Void call() throws Exception {
 405                                 if (!hasValue("styles")) {
 406                                         getValue("styles", Collection.class).set(getStylesByTrack(getId()));
 407                                 }
 408                                 return null;
 409                         }
 410
 411                 });
 412
 413                 /** Memoizer for the remix artists. */
 414                 private final Memoizer<Void> remixArtistsMemoizer = new Memoizer<Void>(new Callable<Void>() {
 415
 416                         @Override
 417                         public Void call() throws Exception {
 418                                 if (!hasValue("remixArtists")) {
 419                                         getValue("remixArtists", List.class).set(getRemixArtistsByTrack(getId()));
 420                                 }
 421                                 return null;
 422                         }
 423
 424                 });
 425
 426                 /**
 427                  * Creates a new track.
 428                  *
 429                  * @param id
 430                  *            The ID of the track
 431                  */
 432                 public LazyTrack(String id) {
 433                         super(id);
 434                 }
 435
 436                 //
 437                 // DEFAULTTRACK METHODS
 438                 //
 439
 440                 /**
 441                  * {@inheritDoc}
 442                  */
 443                 @Override
 444                 public List<Artist> getArtists() {
 445                         artistsMemoizer.get();
 446                         return super.getArtists();
 447                 }
 448
 449                 /**
 450                  * {@inheritDoc}
 451                  */
 452                 @Override
 453                 public Collection<Style> getStyles() {
 454                         stylesMemoizer.get();
 455                         return super.getStyles();
 456                 }
 457
 458                 /**
 459                  * {@inheritDoc}
 460                  */
 461                 @Override
 462                 public List<Artist> getRemixArtists() {
 463                         remixArtistsMemoizer.get();
 464                         return super.getRemixArtists();
 465                 }
 466
 467         }
 468
 469         /**
 470          * {@link ObjectCreator} implementation that can create {@link Track}
 471          * objects. This specific implementation creates {@link LazyTrack}
 472          * instances.
 473          *
 474          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 475          */
 476         private class TrackCreator implements ObjectCreator<Track> {
 477
 478                 /**
 479                  * {@inheritDoc}
 480                  */
 481                 @Override
 482                 public Track createObject(ResultSet resultSet) throws SQLException {
 483                         return new LazyTrack(resultSet.getString("TRACKS.ID")).setName(resultSet.getString("TRACKS.NAME")).setRemix(resultSet.getString("TRACKS.REMIX"));
 484                 }
 485
 486         }
 487
 488         /**
 489          * {@link ObjectCreator} implementation that can create {@link Style}
 490          * objects.
 491          *
 492          * @author <a href="mailto:bombe@pterodactylus.net">David ‘Bombe’ Roden</a>
 493          */
 494         private class StyleCreator implements ObjectCreator<Style> {
 495
 496                 /**
 497                  * {@inheritDoc}
 498                  */
 499                 @Override
 500                 public Style createObject(ResultSet resultSet) throws SQLException {
 501                         return new DefaultStyle(resultSet.getString("STYLES.ID")).setName(resultSet.getString("STYLES.NAME"));
 502                 }
 503
 504         }
 505
 506 }